An Iranian Foreign Ministry official says the Obama administration's offer to consider allowing limited uranium enrichment 'would be a good start.'

TEHRAN — Iranian officials expressed skepticism Saturday about possible Obama administration support for allowing the country to continue enriching some uranium but said it could be a good start for further negotiations on its disputed nuclear program.

Senior U.S. officials have said they might agree to let Iran enrich uranium up to 5% purity if its government agreed to the unrestricted inspections, strict oversight and numerous safeguards that the United Nations has long demanded.

If the deal was offered by all six nations negotiating with Iran and the U.N.'s International Atomic Energy Agency, "it would be a good start," said one official in Iran's Foreign Ministry, who spoke on condition of anonymity.

The United States — along with China, Russia, France, Britain and Germany — began talks with Iran on April 14 in Istanbul, Turkey; the discussions are scheduled to resume May 23 in Baghdad.

"One thing I can tell you for sure is that Iran will never, ever close down the Fordow nuclear site," the official said, referring to the enrichment plant.

"But other issues such as 20% enrichment is open to negotiation. I can say Obama's proposal is good provided it is unanimously echoed."

Iran has produced 210 pounds of 20% enriched uranium for what it says are peaceful purposes, according to the IAEA, but it has purified about six tons at up to 5%, the upper end of the range for most civilian uses. The U.S. and its allies are concerned about more highly enriched uranium because it can be used to make a nuclear bomb.

The Foreign Ministry official said the different behavior of representatives of the negotiating countries — the French envoy was rude, while the U.S. one was surprisingly polite at the Istanbul talks, he said — indicated that they would have difficulty coming to a consensus on this issue.

Any proposal would also face strong skepticism and opposition from leaders in both Iran and the United States.

"Iran has lost a lot by voluntarily accepting the additional protocol for snap visits to nuclear sites before," said Hamid Reza Taraghi of the Islamic Coalition Party, who has close ties to supreme leader Ayatollah Ali Khamenei. "The inspectors of IAEA turned out to be spies and our nuclear scientists were exposed and some of them assassinated."

Only when sanctions on Iran have been lifted and the country's rights as a signatory of the Nuclear Nonproliferation Treaty, which allows countries to enrich uranium for peaceful purposes, are respected will Iran's parliament be prepared to compromise, he said.

It is improbable that Iran would ever agree to stop uranium enrichment altogether for a nuclear program that enjoys wide support among its people. But both hard-liners and reformists in the country would like to see a reduction in tension with Western countries, which have imposed sanctions on Iran's oil industry and central bank.